Congenital midline paraspinal cutaneous markers have been practically linked to the location and nature of neural-tissue lesions. One of the most interesting congenital midline paraspinal cutaneous markers has been the human tail in the lumbosacral region, with underlying spinal dysraphism. Human tails have many shapes and sizes and are usually localized to the lumbosacral region. After a complete neurological examination, the MRI is the most sensitive diagnostic modality to reveal the underlying occult spinal dysraphic state. Surgical excision is aimed at untethering of the spinal cord in symptomatic children and for aesthetic reasons in asymptomatic patients. Here we report an asymptomatic male child with normal external genitilia, whose tail is attached to the gluteal region like an adult phallus and investigations revealed an underlying spinal dysraphic state.

The lumbosacral congenital midline paraspinal cutaneous lesions, which mark an underlying occult spinal dysraphic state, include subcutaneous lipomas, dermal sinuses, human tails, localized hairy tufts, hypertrichiasis, hyperpigmented lesions, aplasia cutis congenita, and even deviated gluteal furrow (DGF). However, tails are the most interesting and fascinating types of cutaneous markers of all. These may be located anywhere in the lumbosacral area, within gluteal furrows, as close as 2.5 cm to the anus and up to the level of the first dorsal spinous process.[1] However, human tails in the gluteal area or of penile shape have not been reported in the literature. The present case report is the first of its kind for its rare, typical phallic shape and its uncommon location, away from the lumbosacral area.

Case Report

A male infant's apprehensive parents presented their child to the Department of Neurosurgery, Sher-i-Kashmir Institute of Medical Sciences (SKIMS), Srinagar Kashmir, with the complaint of baby being born with a second male external genitilia (phallus) of adult size on his left gluteal region, which was surprising and fearful for parents to look at. Further history revealed that it did not increase or decrease in size since birth and was nonerectile and nondischarging.

Clinical examination

The general physical and neurological examination of the child was normal. The child had neither weakness in the legs nor deformity of the feet. There was no incontinence or anal patulousness. The male external genitilia was normal and both the testes were present in the normal scrotum [Figure 1],[Figure 2],[Figure 3]. There was no other congenital anomaly found. The local examination of the lumbosacral and gluteal regions revealed a long, nontender, soft, nonpulsatile, nondischarging, nonfluctuant, normal skin covered adult phallus-like appendage, having glans, meatus, prepuce, scrotum, and shaft, about 12 cm long and 4 cm in diameter at its root [Figure 1],[Figure 2],[Figure 3]. This pseudophallus was attached to the skin- covered, soft plateau-like raised subcutaneous lipoma on the left gluteal area [Figure 3]. The appendage (pseudophallus) was thicker at its root and tapered like a glans-penis at its tip, with the central opening like meatus and a skin covering like the prepuce. The meatus-like opening on the top of the glans-like tip continued as a sinus within the central fibrous tract of the pseudophallus up to the extradural planes. The pseudophallus did not contain any cartilage or bony elements and had no hair on the covering skin, but a central fibrous tract was palpable in the shaft. Moreover, the subcutaneous lipoma forming the edifice of the pseudophallus [Figure 2],[Figure 3],[Figure 4], appeared like a scrotal sac without testicles, and the subcutaneous lipoma further caused deviation of the gluteal furrow (DGF) to the right [Figure 2]. There was a dermal sinus over the upper part of the subcutaneous lipoma, cephalic to the hanging psedophallus [Figure 4].

Investigations

Basic routine investigations like biochemical, ECG, X-ray chest, and so on, were normal. The X-ray lumbosacral and pelvic regions showed bifid spinous processes of L4 and lower down. A sinogram of the pseudophallus (through patent meatus) revealed a wide and dilated sinus tract in the pseudophallus and its extension into the subcutaneous lipoma and extradural planes [Figure 5]. The MRI of the dorsal and lumbosacral areas revealed the low lying (tethered) spinal cord merging with the intradural lipoma, at the L4 vertebral body level, which formed an extension of a huge extraspinal subcutaneous lipoma at the sacrococcygeal level [Figure 6]. The intradural lipomatous component extended from L4 to the sacrococcygeal area [Figure 7].

Management

As a human tail is a congenital benign anomaly with underlying spinal dysraphism, surgical correction is first recommended for aesthetic reasons in asymptomatic patients and for untethering of spinal cord in symptomatic patients. The excision of the gluteal pseudophallus (human tail) was performed in this neurologically asymptomatic child. The intradural lipomatous component with cord-tethering was left to be tackled only if any symptoms arose.

Discussion

The incidence of significant cutaneous lesions along the craniospinal axis in the general population is about 3%, which is much more than the incidence of occult spinal dysraphism.[2] Nevertheless, any midline or paramedian posterior cutaneous anomaly is often the first indication of an underlying dysraphic spinal state and warrants further clinical investigation.[1] The cutaneous signs of spinal dysraphism are seen in 50% of the cases of OSD,[3] although some studies[4] show as high as 86.3% prevalence of cutaneous lesions in OSD. The highly significant and suspicious cutaneous lesions with underlying OSD include hypertrichosis, atypical dimples (>3-5 mm), aplasia cutis, subcutaneous lipoma, hemangiomas, dermal sinuses, deviated gluteal furrow (DGF), dermal appendages in the form of human tails, and so on.[1],[3],[5] Many times two or more of such cutaneous lesions may, not infrequently, coexist and become stronger markers of an underlying OSD. [1],[4] Such lesions occur along the spinal axis and more often in the lumbosacral region.[1] However human tails have been known to exist as true tails or pseudo tails.[6] The true tail contains all types of soft tissues like adipose, muscle vessels, and so on., and a pseudo tail is made of bone, cartilage, and remnants of a notochord.[7]

The cause of such tails has been traced to the disturbance of caudal regression around the sixth week of embryonal life.[8] However, a clear embryogenesis of this malformation, which is associated with intraspinal lipomas, lipomeningomyeloceles, and tethered cord syndromes, is still not understood.[9] The tail may be directly attached to the filum and the spinal cord, which leads to tethering.[8],[9] Surprisingly tail- like subcutaneous lipomas, which are an infrequent form of a human tail, have been a common presentation in a series of 97 children.[10] Literature reveals that 76% (with a range of 43-95%) of patients with OSD have a single or a combination of median or paramedian congenital lumbosacral cutaneous lesions. [11],[12],[13],[14],[15],[16],[17] The case (male child) managed by the Department of Neurosurgery, Sher-i-Kashmir Institute of Medical Sciences, Kashmir, which is reported here, had multiple visible significant cutaneous markers covering an occult spinal dysraphism, revealed by MRI, in the form of a subcutaneous lipoma, dermal sinus, deviated gluteal furrow, and a most fascinating adult phallus-like gluteal tail. This true human tail was atypical in its own way for the reasons of being penile-shaped first, and second, it was ectopic in the location (gluteal). This is the first cutaneous marker of its kind, overlying an OSD, to be reported in the literature. An MRI revealed an underlying OSD, otherwise the appearance of the cutaneous marker pointed to the possibility of the only remnant (phallus) of a conjoined - brother twin.